Rotary duplex pump



1962 s. J. KETTERER ROTARY DUPLEX PUMP 2 Sheets-Sheet 1 Filed Aug. 18, 1960 INVENTOR z TToRN EYS 1962 s. J. KETTERER 3,050,013

ROTARY DUPLEX PUMP Filed Aug. 18, 1960 2 Sheets-Sheet 2 QMEFHIROS I U A INVENTOR m ATTORNES.

3,050,013 ROTARY DUPLEX PUW Stanley J. Ketterer, Stratford, Conn, assignor to The Griffith Company, Bridgeport, Conn, a corporation of Connecticut Filed Aug. 18, 1960, Ser. No. 50,520 Claims. (Cl. 103-149) This invention relates to a rotary type pump, and has for an object to provide an improved pump of the type in which a flexible diaphragm separates similar pump chambers, and in which a rotary operating member is located in the diaphragm and by its rotation shifts the diaphragm back and forth to vary the volumes of the pump chambers to effect the pumping operation.

It is an object of the invention to provide improved means for mounting the flexible diaphragm and effectively sealing it against leakage between the pump chambers, and especially to provide improved means for mounting the flexible diaphragm and incorporating a reinforcing means in the means for mounting the diaphragm.

With the foregoing and other objects in view, I have devised the construction illustrated in the accompanying drawings forming a part of this specification. It is, however, to be understood the invention is not limited to the specific details of construction and arrangement shown, but may embody various changes and modifications Within the scope of the invention.

In these drawings:

FIG. 1 is a vertical transverse section through the pump taken substantially on the line 11 of FIG. 2;

FIG. 2 is a longitudinal vertical section taken substantially on the line 2-2 of FIG. 1;

FIG. 3 is an end view on a reduced scale looking from the left of FIG. 2;

FIG. 4 is an end view on a reduced scale looking from the right of FIG. 2;

FIG. 5 is a section substantially on the plane of the section of FIG. 1 showing the diaphragm in a different position;

FIG. 6 is a section similar to FIG. -1 showing a modified arrangement;

FIG. 7 is an end view of the diaphragm;

FIG. 8 is a side view thereof;

FIG. 9 is a section substantially on line 9--9 of FIG. 8;

FIG. 10 is a side view of the sealing or hinge plate used in the flexible diaphragm;

FIG. 11 is an end view thereof;

FIG. 12 is an end view of the movable member of the check valves, and

FIG. 13 is a side view thereof.

The pump illustrated comprises a housing formed of two end members or bells 1 and 2 between which is mounted an intermediate member or manifold 3. This manifold is provided with a cylindrical chamber 4- which is separated into two separate pump chambers or spaces 5 and 6 by a flexible diaphragm 7 of any suitable material such, for example, as rubber or some rubber-like material, either natural or synthetic rubber, such, for example, as neoprene. This diaphragm is of tubular construction and substantially U-shaped in cross section, as shown in FIG. 9, thus forming a tubular central or intermediate section 8 and outwardly extending flanges 9 at its opposite ends. At diametrically opposite sides of the tubular section 8, it is provided with outwardly extending ribs 10 extending longitudinally between the flanges 9. These ribs are of less height than the flanges 9, as shown in FIG. 8, so that the flanges project somewhat beyond the outer edges of these ribs.

The inner wall of the intermediate member or manifold 3 is provided with a pair of longitudinally extending 3,050,013 Patented Aug. 21, 1962 channels or grooves 11 which extend for the length of the chamber 4 and are arranged on diametrically opposite sides of this chamber, as shown in FIG. 1. The outer edges of the ribs 10 are seated in these grooves or channels and the flanges 9 are tightly clamped between the end members or bells 1 and 2 and the opposite sides of the intermediate member or manifold 3 to make a tight seal for the opposite ends of the flexible diaphragm. A very effective arrangement for this is to provide the opposite ends or sides of the member 3 with a stepped recess 12 in which the flanges 9 are seated and against the bottoms of which they are tightly clamped by the inner ends of the end members 1 and 2, the end members being connected by longitudinally extending bolts or screws 13.

The diaphragm is of smaller diameter than that of the chamber 4 so as to provide the pump spaces or chambers 5 and 6 on opposite sides of the diaphragm. Mounted within the diaphragm is a cylindrical driver 14 which is thus surrounded by the diaphragm, and it is of somewhat larger diameter than the internal diameter of the diaphragm in its normal condition, so that when the driver is inserted in the diaphragm this diaphragm is expanded to tightly grip the driver and is thus held against the driver during operation of the pump and is not drawn away from the driver by suction in the pump chambers during the pumping operation.

Embedded in each of the longitudinal ribs 10 of the diaphragm and extending for the full length thereof is a hinge or sealing plate 15 extending for the full height of each rib, and anchored at its inner edge for hinge action with the driver 14 in the longitudinal groove 16 in the outer surface of the driver. Its outer edge extends to within a short distance of the outer edges of the rib 10 of the diaphragm, and is also anchored at this edge for hinge action during operation of the pump. For this purpose each plate 15 is provided at this edge at each end with an outwardly extending pivot lug =17 seated in sockets 118 in each of the end members 1 and 2. Thus each rib 10 is reinforced for substantially its entire width by this hinge or seal plate, which is anchored at its opposite longitudinal edges in both the driver 14 and the end members 1 and 2 of the housing, and it has hinge action with both the driver 14 and the housing. With this arrangement the only portion of the ribs of the diaphragm which are not reinforced by this member is the relatively thin portions 19 of the diaphragm between the outer edge of this hinge plate and the bottom of the channels 11 in the housing member 3. Therefore, although pressure in the pump chambers tends to force the rubber-like or other flexible material through any unsupported portion of the diaphragm, this is so small that this diaphragm will withstand very high pressures.

For operating the diaphragm in the pumping operation, a shaft 20 extends longitudinally of the housing and has bearing portions 21 and 22 adjacent its opposite ends mounted in suitable bearings 23 and 24- in the end members 1 and 2 respectively, and intermediate these bearings it has an eccentric portion 25 within an elongated or oblong-shaped opening or passage 26 within the driver 14. For better bearing and wearing effect the eccentric is carried in a driver bearing 27 of a diameter equal to the width of the oblong or elongated passage 26 and is on a driver bearing bushing 28 on the eccentric 25. Thus as the shaft and this eccentric rotate it shifts the driver 14 and the enclosing flexible diaphragm laterally back and forth in the pump chamber 4 and the separated chambers 5 and 6, as indicated in FIG. 5, thus varying the volumes of the separated chambers 5 and 6 for the pumping operation. In this action the ribs 10 of the diaphragm are flexed laterally, but the seal between the chambers 5 and 6 is 3 effectively maintained by these ribs and they are effectively reinforced by the seal or hinge plates 15, which are also capable of moving back and forth with the ribs because of the hinge connections at the outer and inner edges of these plates with the housing and the driver 14.

Inlet and outlet passages or conduits for the material being pumped, either gas or liquid, are provided leading to the pump chambers 5 and 6. Thus, an inlet or supply pipe or conduit 29 is connected by passages 30, 31 and 32 with the pump chambers 5 and 6, and exit or discharge passages 33, 34, 35 and 36 connect these chambers with an outlet or discharge conduit 37. In each of these passages are suitable check valves to control the flow of fluid through the passages. Thus in the inlet passages to each of the chambers 5 and 6 is a check valve comprising a tubular seat 38 and a movable valve member 39 having a closed end adapted to seat on one end of this seat and provided with lateral guide fingers guided in a cap member 41 threaded into the intermediate or manifold member 3, with a spring 42 tending to move the valve toward its seat, and the cap may be sealed by a sealing ring 43. Similarly, the outlet passages are controlled by similar valves comprising the seats 44 and similar valves 45 seating on these members having side fingers 46 guided in the cap members 47, and with springs 48 tending to shift them toward the closed position on the valve seats, the cap being sealed by suitable sealing rings 49. The inlet valves 39 are arranged to open with suction in the pump chambers 5 and 6 to permit entrance of fluid to these chambers, and to close under pressure as the volume of these chambers is decreased, while the outlet valves 45 are arranged to open to permit passage of the fluid as the pressure in the chambers 5 and 6 is increased. Thus fluid is drawn into the pump chambers due to increased volume thereof under action of the diaphragm, and the fluid is forced from these chambers under pressure as their volume is decreased.

One of the end members or bells, in this case the memher 2, is provided with an annular oil reservoir 50 extending around the bearing 24 and communicating therewith through passages 51 and 52, leakage around the shaft being prevented by a suitable seal 53. This reservoir is open on the inner side of the end member, and this open side is covered by a disk or plate 54. Suitable flats 55 and 56 may be provided on the shaft to conduct oil from the reservoir to the bearings and the eccentric, the substantial height of the oil level being indicated by the wavy lines 57. This, of course, partly fills the passage 26 with oil, and there may be oil passages 58 from this passage 26 to the space 59 at the end of the shaft which is covered by a sight glass 60 so that the level of the oil may be readily observed, this chamber being sealed by a suitable seal 61 and the glass held in place by a suitable clamping ring 62. Means, such as an oil seal filler cap 63 may be provided to permit supplying oil to the reservoir 50- to maintain the proper oil level therein. The shaft 20 may be operated by any suitable means not shown) such, for example, as a pulley or gear driven from any suitable source of power. The pump may be mounted on any suitable support, such, for example, as a base or housing, or the end member or bell 2 may be secured against a support 64 by suitable bolts or screws threaded into tapped openings 65 in the end member.

In the arrangement of the inlet and outlet passages. of FIG. 1 for the fluid being pumped, the fluid is supplied to the pump chambers 5 and 6 from a single inlet and is forced out through a single outlet. However, as these two chambers are separated from each other, the inlet and outlet passages and control valves therein may be arranged so that each chamber 5 or 6 may be used to pump a different material. Such an arrangement is shown in FIG. 6, in which there is shown two inlets 66 and 67 leading through passages 68 and 69 respectively to the chambers 5 and 6 and each controlled by a check valve 79. Similarly, there are separate outlet passages 71 and 72 from the respective chambers 5 and 6 leading to separate outlets 73 and 74 controlled by the outlet valves 75 and 76. Thus two different materials may be pumped at the same time by this pump with the arrangement of separate inlets and outlets to and from the two pump chambers without changing the construction and arrangement of the flexible diaphragm and its driving means.

It will be seen from the above that the hinge or seal plates 15 being embedded and mounted in the ribs 10 on the outer surface of the flexible diaphragm prevents pressure in the pump chambers 5 and 6 from forcing the rubber-like material at one side of the seal to the other side, as the only place this could happen would be at the outer edges of the seal plates, and it will be seen that this would be a very narrow space. It may be only about an eighth of an inch or less, thus effective for very high pressures. The shaft could be rotated in either direction as its action is to shift the diaphragm back and forth. It is a characteristic of the rubber-like material itself that it will stand very little shear action and fatigues quite rapidly under large flexing, but in this improved construction and arrangement the flexing part of the diaphragm comprising the ribs 10 is effectively reinforced by the seal or hinge plates, and the only place where the flexible material could be forced out under the pressure of the fluid is the very narrow space at the outer edge of these plates. Also the flexing is in only a small section of the flexible material. As the driver is of larger diameter than the normal internal diameter of the diaphragm, the diaphragm is stretched or expanded as it is applied to the driver so the rubber-like material is snug on the driver and the suction on the inlet side therefore does not draw the diaphragm away from the driver. The pump is not limited to pumping liquid but may be used for pumping air or other gas.

Having thus set forth the nature of my invention, I claim:

1. A rotary pump comprising a housing including side and end walls enclosing a pump chamber, a tubular flexible member in the chamber extending between the end walls and of smaller diameter than the chamber so that it is spaced from the side walls and provides with the side and end walls of the chamber pumping spaces on opposite sides of said member, longitudinal diametrically opposite ribs on the outer side of said flexible member, said housing provided with longitudinal grooves in which said ribs are seated and separate the pumping spaces, a driver fitting within and extending longitudinally of the flexible member provided with an elongated longitudinal passage, a rotary shaft extending longitudinally of and provided with an eccentric portion within the elongated passage operating to shift the driver and flexible member back and forth in said pumping spaces to vary the volume thereof, a seal plate embedded in each of said ribs in the flexible member and anchored at one edge for hinge movement in the walls of the housing and at the opposite edge in the walls of the driver, inlet and outlet conduit connections to the pumping spaces, and check valves in said connections controlling inlet and outlet flow of fluid to and from said spaces as their volumes vary by shifting of the flexible member by said eccentric and driver.

2. A rotary pump comprising a housing including spaced end members and a connecting intermediate member enclosing a chamber, a flexible tubular diaphragm located in and extending longitudinally of the chamber to and between the end walls, said diaphragm being of less diameter than the chamber so its outer side walls are spaced from the walls of the chamber, said intermediate member provided with diametrically opposite longitudinal channels on its inner surface, said diaphragm provided with diametrically opposite longitudinal ribs on its outer surface extending between the end members and seated in said channels and dividing said chamber into separate pumping chambers on opposite sides of the diaphragm between the outer surface of this diaphragm and the walls of the chamber, a seal plate embedded in and extending longitudinally of each of said ribs, a driver fitting Within and extending longitudinally of the diaphragm provided with an elongated longitudinal passage, means anchoring one of the opposite edges of the seal plates for hinge movement in the housing and the opposite edge in the driver, fluid intake and discharge connections to said pumping chambers, check valves in said connectionsv controlling fluid fiow to and from said chambers, a longitudinal shaft, bearings mounting the shaft in the end members, and said shaft including an eccentric portion located within the elongated passage in the driver operable to shift the diaphragm in opposite directions in the pumping chambers by rotation of the shaft and eccentric.

3. A rotary pump according to claim 2 in which the diaphragm is a member of rubber-like material including a tubular central portion in which the driver is located, and there are outwardly extending flanges at the opposite ends of said tubular central portion clamped between the end members of the housing and the opposite ends of the intermediate member.

4. A rotary pump comprising a housing including spaced end members and a connecting intermediate member enclosing a chamber, said end members provided with bearing sockets, a flexible diaphragm comprising a central tubular portion extending longitudinally of the chamber and of less diameter than said chamber so as to be spaced from the walls thereof, said intermediate member provided with a pair of longitudinal diametrically opposite channels on its inner surface, said diaphragm provided with a pair of longitudinal diametrically opposite ribs on its outer surface seated in said channels and dividing the space between the diaphragm and the walls of the chamber into separate pumping chambers on opposite sides of the diaphragm, a driver within the diaphragm provided with a longitudinal laterally elongated passage, a longitudinally extending sealing and hinge plate in each of said ribs of the diaphragm provided with pivot lugs extending outwardly from its opposite ends adjacent its outer edge and seated in the bearing sockets in the end members, said driver provided with longitudinal grooves in its outer surface in which the inner edges of said plates are hingedly seated, fluid inlet and discharge connections to the pumping chambers, check valves in said inlet and discharge connections, a rotatable shaft, bearings mounting the shaft in the end members, and said shaft including an eccentric portion in the passage in the driver operable by rotation of the shaft to shift the diaphragm in opposite directions in the pumping chambers to vary the volume thereof.

5. A rotary pump according to claim 4 in which the diaphragm is a member of rubber-like material including outwardly extending flanges at the opposite ends of the tubular portion clamped between the opposite sides of the intermediate member and the end members of the housing, and there is a bearing sleeve member on the eccentric between this eccentric and the driver.

MacCormack Feb. 19, 1952 Waldin July 3, 1956 

